I am in the world of science and I just started primary school this year

Story of: I am in the world of science and I just started primary school this year[Daily plot + single female lead + no system] [If you cannot accept the previous plot, you can jump to Chapter 62, please do not make radical remarks] The killer who was once a member of the organization has now become a child, and just started elementary school this year. Unexpectedly, he met an old friend who he once had a crush on. Haibara Ai: Do you still remember the love letter you wrote? Kobayashi Shouma: Damn! You still kept it? Please don’t take it out, just burn it! Kobayashi Shouma: Why don’t you say I do every time you confess? Haibara Ai: Because if I say that... I won’t hear you asking again!